Methods of cleaning



Filed April 3, 1959 Ev WNJ E352 INVENTOR M W. R/CH TEA United States Patent O 3,007,815 METHODS F CLEANING Melvin W. Richter, Perry Hall, Md., assigner to Western Electric Company, Incorporated, New York, N.Y., a corporation of New York Filed Apr. 3, 1959, Ser. No. 803,934 2 Claims. (Cl. 134-15) The present invention relates generally to methods of cleaning, yand particularly to `cleaning methods wherein an article to `be cleaned is advanced successively through cleaning, rinsing and drying bath Accordingly, an object of the invention is to provide new and improved methods of cleaning.

Another object of the invention is to provide new and improved methods of cleaning an article, wherein the article passes in succession through cleaning, rinsing and drying baths.

A further `object of the invention is to provide methods of cleaning jacketed cordage by advancing the same along an undulating path through cleaning, rinsing and drying baths.

The above and other objects are accomplished, according to certain features of the invention, by providing a cleaning bath including a .layer of a detergent solution and a layer of a liquid metal, one layer floating on the other in surface Contact therewith. Preferably, the metal is mercury and the layer of detergent solution floats thereon. A rinsing bath may also be provided consisting of a layer of water ilo-ating on and in surface contact with a layer of a liquid metal, such as mercury. In addition, a drying bath may be provided consisting of a pool of a liquid metal, such as mercury. The article to be cleaned is advanced along an undulating path for one or more passes through the various layers `of the cleaning, rinsing and drying baths.

Other objects, advantages and features of the invention will appear from the following detailed description, when read in conjunction with the `appended drawing, in which the single figure constitutes a vertical section through a series of cleaning, rinsing and drying baths.

Referring now in detail to the drawing, a length of jacketed cordage (e.g., polyvinyl-chloride jacketed cordage used in the communications industry for the manufacture of telephone cords) to be cleaned is continuously advanced, generally from left to right, along an undulating path over and under a succession of guide pulleys 11-11. The cordage lil passes first through a cleaning bath, designated generally by the numeral 12, then through a rinsing bath, designated generally by the numeral 13, and finally through a drying bath, designated generally b-y the numeral 14.

The cleaning bath 12 includes a container or tank 16 having an upper layer 17 of a suitable liquid detergent solution therein, which layer floats on and is in surface contact with a lower layer 13 of a suitable liquid metal, such as mercury. The intermediate pulleys 11-11 are preferably immersed in the `liquid layers 17 and 18 so that the cordage 10 remains submersed during its entire travel through the bath 12 `and so that the cordage exes as it passes around the pulleys 11-11. The rinsing bath 13 is generally similar in arrangement to the cleaning bath 12, and includes a tank 19 containing an upper layer 21 of a rinsing liquid, such as Water, iioating on and in surface contact with a lower `layer 22 of a liquid metal, such as mercury. The drying bath 14 `comprises simply a tank 23 containing a pool 24 of a liquid metal, such as mercury.

The metal used may be any metal which is: (l) liquid at the temperature to be employed; (2) nonreactive with and preferably nonadherent to Ithe article being cleaned:

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and (3) nonreactive and immiscible with the detergent solution. Preferably, a metal is used which is liquid at or slightly Yabove room temperature, such as `ga-lliurn or mercury, with mercury being preferred for most applications, since it is liquid at most temperatures which would be encountered and requires no external hea-ting. For some applications, it might lbe preferred to utilize lo-w melting eutectic mixtures of metals. If the metal is heated, then the detergent utilized must not boil or be adversely `affected by the temperatures required.

When discrete articles are to be cleaned, they may be dipped into or carried on a conveyor through the treating baths. When a continuous length of cordage 10 is being cleaned, it is advanced continuously through the baths as illustrated. As the cordage 1t) passes through the detergent layer 17, it is wetted by the detergent to remove foreign matter therefrom, in conventional fashion. In the preferred arrangement illustrated, the flexing of the cordage lll as it passes around the upper pulleys 11-11 assists in enabling the detergent to wet the surfaces of the cordage and in the breaking -away of foreign matter loosened by the detergent.

The mercury does not wet the cordage 10 so that, as the cordage passes through the interface between the detergent layer 17 and the mercury layer 18, the mercury acts as `a wiping die to remove the detergent and any loosened particles from the cordage and maintains the cordage dry until it next passes rin to the detergent layer 17. In `any given application, an `optimum speed range to provide a desired degree of cleaning should be determined. Any detergent which might be carried into the `mercury layer 18 immediately rises back to the interface.

The cordage 10 emerges dry from the mercury layers 18 and 22 in the cleaning and rinsing baths 12 :and 13, respectively, after each pass, and is then wetted again in both baths by the cleaning and rinsing layers 17 and 21, respectively. Upon emerging from the drying bath 14, the cordage 10 is substantially dry and is ready for use. Any traces of mercury which might adhere to the cordage 10 may be wiped od by suitable means (not shown).

In the drwng bath 14, water carried on the surface of the cordage 10 from the rinsing bath 13 is stripped or wiped therefrom by the die action of the mercury. In time, a layer of water 26 will build up on the surface of the mercury pool which, if preventative measures were not taken, would impair the efficacy of the drying bath 14 by again wetting the cordage 1G as it emergen therefrom. Accordingly, means, designated generally by the numeral 27, are provided, associated with the drying bath 14, for preventing any accumulation of water on the surface of the pool of mercury 24 in the vicinity of a point A where the cordage 10 emerges from the pool 24.

The means 27 may comprise a vertical divider plate 28 extending across the entire front-to-back width of the tank 23 and bolted between the back side 29 of the tank 23 and the front side (not shown). The plate 27 extends vertical-ly an appreciable distance above the mercury level and a considerable dist-ance therebelow, preferably almost to the bottom o-f the tank 23. Thus, it will be apparent that the plate 28 divides the pool 24 into an entrance chamber B at the left of the tank 23 and an exit chamber C at the right of the trank, which chambers are connected only at the bottom.

With this arrangement, as the cordage 10 enters the pool 24 at a point D in the =left chamber B, the Water' carried thereby will be stripped therefrom and will accumula-te into the layer 26 which, because of the divider plate 28, will be confined to the surface of the left chamber B. The reason for extending the plate 28 for a considerable distance down into the pool 24 is to prevent any water, which when carried by the cordage 10 down Patented Nov. 7, 1961 into the pool 24 and then released therefrom will rise tothe surface of the left chamber B, from being carried over into the right chamber C. A drain pipe 31 is also provided, connnunicaitng with the left chamber B a short distance above the surface of the pool 24 so as to drain away excess water from the surface. of the layer 26.

The detergent liquid may beany suitable cleaning maten'al which is immiscible w-ith the mercury or other metal used and which will accomplish the desired cleaning of the article. A suitable `cleaner for polyvinyl-chloride jacketed cordage comprises an aqueous solution of IgepaL a nonionic polymerized ethylene oxide condensation product manufactured by the General Dyestuff Corporation of New York.

It is preferable to use la detergent layer 17 which is lighter than the metal layer 1S so as to iloat thereon, although it would also be possible to operate the process with a relatively light metal floating on the surface of a relatively heavy layer of :a cleaning solution.

While a specific embodiment of the invention has` been 20 describedv hereinabove, it will be obvious that various modifications may be made from the specific details described without departing from the spirit and scope of the invention.

What is claimed is:

1. The method of cleaning an article, which comprises the steps of passing the article through successive layers of a detergent solution and -a liquid met-al in surface contact with each other, then passing the article through successive layers of Water and a Iliquid metal in surface contact with each other, and nally passing the article through a pool of a liquid metal.

2. The method of cleaning a length of jacketed cordage, which comprises the steps of ladvancing the cordage along an undulating path: rst, Ifor a number of passes through the various layers of a cleaning bath consisting of a layer of detergent solution floatingon' and in surface contact with a layer of liquid mercury; second, for at least one pass through a rinsing bath consisting of a layer of water floating on and in surface contact with a layer of liquid mercury; and, finally, for at least one pass through a pool of liquid mercury.

References Cited in the tile of this patent UNITED STATES PATENTS 739,140 Baker Sept. 15, 1903 1,595,237 Minton Aug. l0, 1926 1,863,254 Polin June 14, 1932 2,390,007 Sherman Nov. 27, 19.45 2,458,394 Luboshez Jian. 4, 1949 2,693,995 Hannay Nov. 9, 1954 

1. THE METHOD OF CLEANING AN ARTICLE, WHICH COMPRISES THE STEPS OF PASSING THE ARTICLE THROUGH SUCCESSIVE LAYERS OF A DETERGENT SOLUTION AND A LIQUID METAL IN SURFACE CONTACT WITH EACH OTHER, THEN PASSING THE ARTICLE THROUGH SUCCESSIVE LAYERS OF WATER AND A LIQUID METAL IN SURFACE CONTACT WITH EACH OTHER, AND FINALLY PASSING THE ARTICLE THROUGH A POOL OF A LIQUID METAL 